Hoist with trailer hitch attachment

ABSTRACT

A hoist for vehicles such as pickup trucks and sport utility vehicles is described. The hoist engages a standard trailer hitch and when erect allows loading of the trailer. Additionally, when used with a vehicle having a tailgate the hoist does not interfere with the normal operation of the tailgate. The hoist also features structural supports that are deployed to contact the ground thereby reducing the stress on trailer hitch and some structural members of the hoist.

FIELD OF THE INVENTION

[0001] This invention relates to hoists and cranes mounted to vehicles and particularly to hoists that use a trailer hitch as a structural attachment.

BACKGROUND OF THE INVENTION

[0002] Pickup trucks are versatile vehicles used for hauling cargo. Many pickup trucks are used by businesses for delivering merchandise and transporting goods. Often the cargo transported is not easily loaded and unloaded. When people make the effort to load and unload heavy goods from the raised bed of a pickup truck they risk personal injury, particularly to the lower back.

[0003] In order to help people load and unload cargo from small trucks, a variety of small hoists suitable for attachment to a conventional trailer hitch have been developed. For example, in U.S. Pat. No. 4,746,263, Cook describes a small retractable hoist. This hoist is mounted to the bumper of a pickup truck and, when it is not needed, is stored in the bumper. This hoist is compact and versatile however the truck directly supports the load that the hoist lifts. Clearly, if heavy loads are to be lifted then the structure of the truck proximate the bumper should be reinforced. Otherwise, the structural supports for the bumper are being used in a way that they were not intended and in the event that a very heavy load is lifted, the crashworthiness of the truck may be compromised.

[0004] In U.S. Pat. No. 4,419,038, Pendergraft also teaches a hoist design for a small truck. The hoist taught by Pendergraft also folds into a large rear vehicle bumper. This hoist optionally features structural supports that increase the effective width of the truck when the hoist is properly deployed. Although this hoist has the potential to be very sturdy, it also is likely to be very costly. Additionally, the hoist taught by Pendergraft is raised from one side of the truck. Clearly, this would be inconvenient if it were necessary to load the truck from the opposite side.

[0005] In U.S. Pat. No. 4,226,331, Dumond teaches the design of a hoist for use with a three-point hitch of a tractor. This design uses hydraulic actuators for movement. The hoist is notable in that it features supports that contact the ground proximate the load bearing member of the hoist. This structure complicates the mounting of a trailer to the tractor when the hoist is deployed.

[0006] In U.S. Pat. No. 6,042,328, McVaugh demonstrates a lifting device for a small truck that is shown attaching directly to a trailer hitch attachment. The lifting device is shown spanning a considerable length of the bed of the truck. Since this device does not include an external support, the weight of the lift and any load that it carries are supported exclusively by the trailer hitch. A lifting device of this type produces substantial torque at the trailer hitch attachment. Unless the trailer hitch is designed to bear this type of load it is most probable that the trailer hitch is damaged when the lift is used.

[0007] It would be beneficial to have a small, cost effective hoist for pickup trucks that is easily transportable, supports heavy loads and does not involve a costly structural modification to the pickup trucks. Additionally, it would be beneficial that such a hoist be collapsible for ease of storage.

SUMMARY OF THE INVENTION

[0008] The invention describes a hoist kit for a trailer hitch attachment, comprising:

[0009] a hoist mount having a first end, a second end and a hinged joint disposed therebetween for providing rotational approximately lateral movement of the second end relative to the hinged joint when the first end is fixed, the first end for mechanically engaging the trailer hitch;

[0010] a boom support for extending approximately vertically, said boom support for being mechanically coupled to the second end of the hoist mount;

[0011] a boom for extending from the boom support, said boom for bearing a weight of an external load; and,

[0012] a first leg for being mechanically coupled proximate the second end of the hoist mount for pivotal motion relative thereto between a first position for contacting a region of ground proximate a vehicle supporting said trailer hitch attachment and for structurally supporting the hoist mount and a second retracted position.

[0013] Further, the invention discloses a hoist for a trailer hitch attachment, comprising:

[0014] a hoist mount having a first end for mechanically engaging a trailer hitch receiver, a second end and a hinged joint disposed therebetween for providing rotational approximately lateral movement of the second end relative to the hinged joint when the first end is fixed;

[0015] a boom support extending approximately vertically, said boom support mechanically coupled to the second end of the hoist mount;

[0016] a boom extending from the boom support, said boom for bearing a weight of an external load; and,

[0017] a first leg mechanically coupled proximate the second end of the hoist mount for pivotal motion relative thereto between a first position for contacting a region of ground proximate a vehicle supporting said trailer hitch attachment and for structurally supporting the hoist mount and a second retracted position.

[0018] Additionally, the invention details a hoist for a trailer hitch attachment, comprising:

[0019] a hoist mount having a first end, a second end and a hinged joint disposed therebetween for providing rotational approximately lateral movement of the second end relative to the hinged joint when the first end is fixed, the first end for mechanically engaging the trailer hitch;

[0020] a boom support for extending approximately vertically, said boom support mechanically coupled to the second end of the hoist mount;

[0021] a boom extending from the boom support, said boom for bearing a weight of an external load; and,

[0022] a first leg coupled to one of said boom and said boom support for engaging the ground and for supporting the boom and a load supported thereby.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The invention will now be described with respect to the drawings in which:

[0024]FIG. 1 is a side view of an erected hoist according to a first embodiment of the invention;

[0025]FIG. 2 is a side view of a hoist according to a first embodiment the invention attached to a pickup truck in which the pickup truck has a trailer attached;

[0026]FIG. 3 a top view of a hoist according to a first embodiment the invention attached to a pickup truck demonstrating the working areas of the hoist;

[0027]FIG. 4 is a side view of the hoist according to a first embodiment the invention with the boom folded parallel to the boom support;

[0028]FIG. 5 is a side view of the hoist according to a first embodiment the invention with the legs retracted;

[0029]FIG. 6 is a side view of the hoist according to a first embodiment the invention with boom folded, the legs retracted and the boom support folded over the hoist mount;

[0030]FIG. 7 is an exploded top view of an embodiment of the mechanism that allows the boom support to rotate relative to the hoist mount;

[0031]FIG. 8 is a side view of the mechanism of FIG. 7 showing the ball connected to the hoist tongue;

[0032]FIG. 9 is a side view of the trailer hitch attachment according to the invention;

[0033]FIG. 10 is a side view of the hoist according to a first embodiment the invention being used as a winch;

[0034]FIG. 11 is an isometric view of the hoist according to the invention;

[0035]FIG. 12 is a side view of a variation of the hoist according to the invention with a mechanism to compensate for the changes in vehicle height as the vehicle is loaded, and;

[0036]FIG. 13 is an isometric view of a hoist according to a second embodiment of the invention featuring a wheel and a foot for structural support.

DETAILED DESCRIPTION OF THE INVENTION

[0037] The varieties of hoist mechanisms for light trucks usually fall into one of two categories. A first category comprises light hoists that extend from the truck. A second category comprises hoists that have their own structure and support heavy loads using the truck to enhance their stability. Hoists in the second group are likely to be bulky and heavy themselves.

[0038] Referring to FIG. 1 a hoist according to a first embodiment of the invention is shown. The hoist includes a boom 15 with an extendable section 16. A jib post 8 allows the boom support 14 to rotate 360°. The jib post 8 is connected to the boom support 14 with a collar 13 proximate the base of the boom support 14. The top end of the jib post 8 includes a jib pin 12 that is welded to a plate. The plate also connects the jib post 8 to the boom support 14. Legs 9 support the jib post 8. The legs are held in place by adjustable links 11. Additionally the jib post 8 is supported by an attachment (not shown) that connects to a standard trailer hitch. Each of the legs 9 has a foot 10 for contacting the ground. FIG. 1 shows the legs 9 extended equally as though the hoist is on level ground. Clearly, this is not always the case and the legs 9 are easily adjusted for somewhat uneven terrain. This embodiment of the hoist is shown with a hook 19 at the end of the cable 18.

[0039] Referring to FIG. 2, a hoist according to the invention is shown attached to a trailer hitch 35 mounted to a pickup truck 32. A trailer 33 is mounted on the hoist ball of the hoist. The hoist is mated to the receiver hitch of the pickup truck 32. FIG. 2 is highly illustrative of one of the critical advantages of the invention. The hoist according to the invention does not interfere with tailgate of the pickup truck 32 or the use of the trailer hitch for supporting a trailer. Thus, the hoist is usable for loading the pickup truck 32 as well as the trailer 33. Two feet 10 connected to the legs 9 as well as the trailer hitch 35 support the hoist. Thus, the hoist is supported at three locations that provide it with considerable stability in comparison with a single point support. The boom support 14 is rotated to the correct position for accessing either the trailer 33 or the pickup truck 32. The winch 17 contains a sufficient length of cable to ensure easy access to the load from the ground or the vehicles. The feet 10 along with the trailer hitch attachment form a triangle when viewed from above. A person of skill in the art of structural design will be aware that this design provides excellent stability. In comparison, a hoist according to the teaching of McVaugh in U.S. Pat. No. 6,042,328 would require considerable structural reinforcement resulting in a substantially heavier hoist. Although the hoist is shown attached to a pickup truck this need not be the case. Since the hoist will load the trailer it is useable with any vehicle that has a standard trailer hitch attachment. In other words, a car with a trailer hitch attachment is able to use the hoist to load heavy objects into the trailer.

[0040] Referring to FIG. 3, a top view of the hoist according to the first embodiment of the invention is provided. This view demonstrates the arc A traced by the jib pin 12 as the hoist is rotated about the ball 29 of the trailer hitch assembly. By rotating this way the hoist is able to load a first side of the pickup truck 32 and then be swiveled to the second other side for loading that side. The swiveling operation is easily carried out when the hoist is unloaded and the feet (not shown in this view) are partially retracted. The arcs B, C and D represent suggested working areas for the hoist where the hoist is able to structurally support a load.

[0041] Referring to FIG. 4, the hoist according to the first embodiment of the invention is shown in a partially folded position. The boom 15 has been rotated to be parallel to the boom support 14. The legs 9 have been retracted resulting in a compact assembly. Various rotational joints are structurally supported with pins 1 c, 1 d, 1 f and 1 h. Pulleys 34 are used shown for supporting a cable that is used to support a load when the hoist is erected. A tongue support bracket 36 and pin 37 hold the partially folded hoist in position preventing rotation at the location of the pin 37 when the pin 37 is properly coupled to the hoist. The extension 6 is mechanically coupled to a trailer hitch attachment. The ball 29 of the trailer hitch attachment includes a hoist mount pivot pin 5 with a threaded end. Clearly, other methods of supporting the extension are easily envisioned by one of skill in the art of mechanical design. This view clearly illustrates the plates 8 a attached to the jib post 8 that support the legs 9. A flat bar 25 helps to maintain the jib post vertically oriented when the hoist is being erected.

[0042] Referring to FIG. 5, a side view of the partially folded hoist is shown. This view clearly illustrates the position of the feet 10 and legs 9 in the folded position. The hoist mount 3 includes a mating end 35 for attachment to a trailer hitch.

[0043] Referring to FIG. 6, the partially folded hoist has been brought down parallel to the extension 6 for stowing parallel to the bumper of the pickup truck. The attachment to the trailer hitch secures the fully folded hoist against the bumper of the pickup truck preventing it from rotating inadvertently. The slider body sides 22 maintain the jib post 8 parallel to the hoist tongue 6.

[0044] Referring to FIG. 7 and FIG. 8 a detail of an exemplary release mechanism is shown. The release mechanism permits the rotation shown in FIG. 6. FIG. 7 includes a pole pin 1 b having a bent handle the straight end of which is held in place with a cotter pin. Additionally, a slider pin assembly 23 is also held in place with cotter pins. The slider pin assembly 23 and the pole pin 1 b are used to support the jib post in the erect position. When jib post is erected, a drawing bolt assembly 21 is tightened from the access hole 26 to help stiffen the hoist. The hoist tongue 6 is coupled to the hoist mounting plate 4 with a hoist mount pivot pin 5. The hoist tongue 6 has a bracket 7 at one end for connection with the hoist mount pivot pin 5. The hoist mount 3 also has a bracket 4 for connection with hoist mount pivot pin 5. This connection allows the hoist tongue 6 to rotate relative the hoist mount 3 allowing the hoist to be positioned on either side of the trailer hitch.

[0045] Referring to FIG. 9 a detail view of an exemplary trailer hitch attachment is shown. It should be noted that the use of the hoist does not interfere with the trailer provided there is no need to move the hoist to the other side of the truck. If it is necessary to move the hoist to the other side of the truck then it is a simple matter to disconnect the hoist and reattach it on the side where it is needed. The hoist mount pivot pin 5 is shown fastened at one end with a washer 28 and a nut 27 and fastened by the ball 29 having internal threads. Optionally, the hoist mount pivot pin 5 has a shoulder that contacts the side opposite the ball 29 of the bracket 7. Also, a second shoulder is optionally added proximate the nut to prevent compression of the bracket 7. Clearly, a variety of options are optionally employed to keep the hoist mount pivot pin 5 in position.

[0046] Referring to FIG. 10 a hoist according to an embodiment of the invention is shown. In this view the hoist is used as a winch for dragging a load closer to the hoist to permit safe loading. Alternatively, the hoist is used to move the pickup truck if the pickup truck should become stuck. A person of skill in the art of structural design will be aware that the hoist is best suited to lifting loads proximate the boom support 14. By pulling the load closer to the hoist the amount of stress on the hoist when the load is lifted is reduced substantially.

[0047] Referring to FIG. 11, a hoist according to the invention is shown clearly illustrating the relative position of the hoist with respect to a pickup truck used to support it. The hoist is shown in a position to load or unload an item from the box of the pickup truck. As can be seen, in this orientation the hoist does not interfere with the tailgate of the pickup truck.

[0048] Referring to FIG. 12 an alternative mechanism for the hoist tongue is presented. This mechanism permits the suspension of the vehicle to react to the loading and unloading of the vehicle and an optionally attached trailer. The mechanism includes a short tongue 42 connected to the ball 29 of the trailer hitch assembly. The short tongue 42 is connected to a lower linkage 39 and an upper linkage 40. The lower linkage 39 and the upper linkage 40 are also connected to the long tongue 42 a. The lower linkage 39 includes a stop feature 38 that limits the raising of the short tongue 42. The upper linkage 40 and the lower linkage 39 are mechanically coupled to the short tongue 42 and the long tongue 42 a with pivot pins 41. This linkage is particularly advantageous because it permits the vehicle suspension to react to the loading of the vehicle and trailer without imparting high stress loads to the hoist. The mechanism supports the hoist such that as the vehicle is loaded, the hoist remains roughly vertical.

[0049] Referring to FIG. 13 another embodiment of the invention is shown. In this embodiment the hoist incorporates a wheel 50 attached to the leg of the hoist. The wheel 50 is permitted to rotate about the boom support 14 in order to better support the load. As the boom 15 is rotated, the leg with the wheel 50 rotates and the wheel 50 remains well positioned to the assist in supporting the weight of the load. To further reinforce the hoist, a foot 60 is deployed to contact the ground below the jib post 8. In this way, the hoist is able to support heavy loads without causing high loads on the trailer hitch. Clearly, this embodiment is easily modified so that the wheel 50 and the foot 60 are supported by separate legs and, optionally, the design is modified to include more than one wheel. When more than one wheel is incorporated, it is suggested that the wheels be arranged to ensure that at least one wheel is located on either side of the boom thereby further enhancing the stability to the hoist.

[0050] Another embodiment of the invention features a leg that extends directly downward from the jib post. This leg is set in position prior to loading the hoist. This configuration also provides enhanced structural stability for the hoist without adding a large amount of weight.

[0051] Still another embodiment of the invention features a combination of the different leg and wheel configurations to support the jib post structure.

[0052] A variety of different embodiments of the invention incorporate different types of actuators. For example, a simple version of the hoist relies on manual input to raise and lower loads for the hoist. Another embodiment of the invention uses an electric winch that draws current from the battery of the vehicle. Still another embodiment of the invention incorporates a hydraulic winch. Also, the various joints of the hoist are optionally hydraulically actuated. Clearly a hoist according to the invention optionally incorporates any of these actuators or a combination of different actuators.

[0053] Variations in the design of a hoist according to the invention include using hydraulically actuated joints or, alternatively electrically actuated joints. Similarly, the winch used for lifting is optionally hand powered, hydraulic or electrically driven. Additionally, the hoist is optionally modular allowing individual components to be modified for specific tasks and substituted as necessary. For example, if the hoist is to be used in areas with very soft terrain then size of the members used to contact the ground are easily increased and substituted for the standard members.

[0054] Of course, though the legs are described herein as retracting, it is possible to implement the hoist with a fixed leg. Here the leg would support motion of the boom about the boom support. That said, it is a straightforward matter to design a leg that is slightly shorter than what is needed to support the boom support absent the boom being in place. As such, the leg is installed before the boom and the additional weight of the boom causes the leg to engage the ground and provide additional support. Of course, the hoist is also implementable with a leg that is driven toward the ground by the weight of the load and so forth.

[0055] Clearly, the embodiments presented herein are meant to be illustrative of the invention and not limiting the invention to the embodiments disclosed. Numerous other embodiments of the invention will be apparent to one of skill in the art of hoist design without departing from the spirit and the scope of the invention. 

What is claimed is:
 1. A hoist kit for a trailer hitch attachment, comprising: a hoist mount having a first end, a second end and a hinged joint disposed therebetween for providing rotational approximately lateral movement of the second end relative to the hinged joint when the first end is fixed, the first end for mechanically engaging the trailer hitch; a boom support for extending approximately vertically, said boom support for being mechanically coupled to the second end of the hoist mount; a boom for extending from the boom support, said boom for bearing a weight of an external load; and, a first leg for being mechanically coupled proximate the second end of the hoist mount for pivotal motion relative thereto between a first position for contacting a region of ground proximate a vehicle supporting said trailer hitch attachment and for structurally supporting the hoist mount and a second retracted position.
 2. A hoist kit according to claim 1, comprising a second leg for being mechanically coupled proximate the second end of the hoist mount for pivotal motion relative thereto between a first position for contacting a region of ground proximate a vehicle supporting said trailer hitch attachment and for structurally supporting the hoist mount and a second retracted position such that when the hoist mount is engaged with the trailer hitch and the hoist is assembled with the first leg in the first position and the second leg in the first position, the boom support is within a triangle formed by the first end of the hoist mount, the region of ground contacted by the first leg and the region of ground contacted by the second leg.
 3. A hoist kit according to claim 1, wherein when the trailer hitch is mounted to a vehicle having a driver side and a passenger side, the vehicle having a main axis extending between a front end of the vehicle and a rear end of the vehicle about a centerline of the vehicle, said vehicle having a tailgate, said tailgate having an open position and a closed position and when assembled, the hoist does not interfere with the tailgate when the tailgate is in the open position when the hoist is optionally positioned away from the main axis of the vehicle on either of the driver's side and the passenger's side of the vehicle.
 4. A hoist kit according to claim 1, wherein the first leg comprises a wheel wherein in the first position said wheel contacts a region of ground proximate a vehicle supporting said trailer hitch attachment for structurally supporting the hoist mount and wherein in the second retracted position said wheel other than contacts the region of ground.
 5. A hoist kit according to claim 2, wherein the first leg comprises a wheel wherein in the first position said wheel contacts a region of ground proximate a vehicle supporting said trailer hitch attachment for structurally supporting the hoist mount and wherein in the second retracted position said wheel other than contacts the region of ground wherein the second leg comprises a second wheel wherein in the first position said second wheel contacts another region of ground proximate a vehicle supporting said trailer hitch attachment for structurally supporting the hoist mount and wherein in the second retracted position said second wheel other than contacts the second region of ground, and wherein an angle between the first leg and the second leg is substantially constant when said first leg is in the first position and said second leg is in the first position.
 6. A hoist kit according to claim 1, wherein the first leg comprises a wheel wherein in the first position said wheel contacts a region of ground proximate a vehicle supporting said trailer hitch attachment for structurally supporting the hoist mount and wherein in the second retracted position said wheel other than contacts the region of ground and, wherein in the first position the first leg moves laterally rotationally in approximate co-ordination with the boom.
 7. A hoist kit according to claim 1, comprising a second leg for being mechanically coupled proximate the second end of the hoist mount for pivotal motion relative thereto between a first position for contacting a region of ground proximate a vehicle supporting said trailer hitch attachment and for structurally supporting the hoist mount and a second retracted position such that when the hoist mount is engaged with the trailer hitch and the hoist is assembled with the first leg in the first position and the second leg in the first position, the boom support is within a triangle formed by the first end of the hoist mount, the region of ground contacted by the first leg and the region of ground contacted by the second leg.
 8. A hoist for a trailer hitch attachment, comprising: a hoist mount having a first end for mechanically engaging a trailer hitch receiver, a second end and a hinged joint disposed therebetween for providing rotational approximately lateral movement of the second end relative to the hinged joint when the first end is fixed; a boom support extending approximately vertically, said boom support mechanically coupled to the second end of the hoist mount; a boom extending from the boom support, said boom for bearing a weight of an external load; and, a first leg mechanically coupled proximate the second end of the hoist mount for pivotal motion relative thereto between a first position for contacting a region of ground proximate a vehicle supporting said trailer hitch attachment and for structurally supporting the hoist mount and a second retracted position.
 9. A hoist according to claim 8, comprising a second leg mechanically coupled proximate the second end of the hoist mount for pivotal motion relative thereto between a first position for contacting a region of ground proximate a vehicle supporting said trailer hitch attachment and for structurally supporting the hoist mount and a second retracted position such that when the hoist mount is engaged with the trailer hitch and the hoist is assembled with the first leg in the first position and the second leg in the first position, the boom support is within a triangle formed by the first end of the hoist mount, the region of ground contacted by the first leg and the region of ground contacted by the second leg.
 10. A hoist according to claim 8, wherein when the trailer hitch is mounted to a vehicle having a driver side and a passenger side, the vehicle having a main axis extending between a front end of the vehicle and a rear end of the vehicle about a centerline of the vehicle, said vehicle having a tailgate, said tailgate having an open position and a closed position and when assembled, the hoist does not interfere with the tailgate when the tailgate is in the open position when the hoist is optionally positioned away from the main axis of the vehicle on either of the driver's side and the passenger's side of the vehicle.
 11. A hoist according to claim 8, wherein the first leg comprises a wheel wherein in the first position said wheel contacts a region of ground proximate a vehicle supporting said trailer hitch attachment for structurally supporting the hoist mount and wherein in the second retracted position said wheel other than contacts the region of ground.
 12. A hoist according to claim 9, wherein the first leg comprises a wheel wherein in the first position said wheel contacts a region of ground proximate a vehicle supporting said trailer hitch attachment for structurally supporting the hoist mount and wherein in the second retracted position said wheel other than contacts the region of ground wherein the second leg comprises a second wheel wherein in the first position said second wheel contacts another region of ground proximate a vehicle supporting said trailer hitch attachment for structurally supporting the hoist mount and wherein in the second retracted position said second wheel other than contacts the second region of ground, and wherein an angle between the first leg and the second leg is substantially constant when said first leg is in the first position and said second leg is in the first position.
 13. A hoist according to claim 8, wherein the first leg comprises a wheel wherein in the first position said wheel contacts a region of ground proximate a vehicle supporting said trailer hitch attachment for structurally supporting the hoist mount and wherein in the second retracted position said wheel other than contacts the region of ground and, wherein in the first position the first leg moves laterally rotationally in approximate co-ordination with the boom.
 14. A hoist according to claim 8, comprising a second leg mechanically coupled proximate the second end of the hoist mount for pivotal motion relative thereto between a first position for contacting a region of ground proximate a vehicle supporting said trailer hitch attachment and for structurally supporting the hoist mount and a second retracted position such that when the hoist mount is engaged with the trailer hitch and the hoist is assembled with the first leg in the first position and the second leg in the first position, the boom support is within a triangle formed by the first end of the hoist mount, the region of ground contacted by the first leg and the region of ground contacted by the second leg.
 15. A hoist for a trailer hitch attachment, comprising: a hoist mount having a first end, a second end and a hinged joint disposed therebetween for providing rotational approximately lateral movement of the second end relative to the hinged joint when the first end is fixed, the first end for mechanically engaging the trailer hitch; a boom support for extending approximately vertically, said boom support mechanically coupled to the second end of the hoist mount; a boom extending from the boom support, said boom for bearing a weight of an external load; and, a first leg coupled to one of said boom and said boom support for engaging the ground and for supporting the boom and a load supported thereby.
 16. A hoist according to claim 15, wherein the first leg comprises a wheel for supporting rotational movement of the boom while maintaining support thereof.
 17. A hoist according to claim 16, wherein the wheel is disposed for rotation in a plane parallel to a plane of instantaneous motion of the boom when the boom is being moved about the boom support.
 18. A hoist according to claim 17, wherein the wheel is a fixed wheel that other than swivels about an approximately vertical axis.
 19. A hoist according to claim 17, wherein the wheel is for swiveling about an approximately vertical axis. 